离心泵输送的液体黏度增大时,性能曲线最先变化的是()。A.扬程降低 B.轴功率增加 发布时间:2017-07-18 13:02 │ 来源:www.tikuol.com 题型:单项选择题 问题: 离心泵输送的液体黏度增大时,性能曲线最先变化的是()。A.扬程降低B.轴功率增加C.效率降低D.B和C
题型:单项选择题 The chair is made______wood and the paper is made ______wood,too [ ]A. of; of B. from; of C. of; from D. from; from 查看答案